==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.0
- Linux/BSD distribution name and version: Ubuntu 14.04 LTS
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): LDAP
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? yes
- Related log if you're reporting an issue:
====
Hello guys,
some of my employees complained that they are not receiving mails with attachment and sometimes it take about 2 hours to get that mails , there is 2 mail back ends in my environment Office365 and Iredmail
this happens when we send from Office365 to iredmail
when I did message trace from the office365 side the message status is :
Message size: 3639 KB
Status :Pending
Reason : 451 4.4.0 SMTPSEND.SuspiciousRemoteServerError: remote server disconnected abruptlyl; retry will be delayed. OutboundProxyTargetIP:*****(My Iredmail Server IP). OutboundProxyTargetHostNamet: *******.net